It deserved a C or worse because it was not very well prepared.
From Smith: "Today the paper is kind of famous, and it's because of a careless comment I once made. I was asked what grade I got on it, and I stupidly said 'I guess I got my usual gentlemanly C.' That stuck and it's become a well-known story because everybody likes to flout authority. But to be honest, I really don't remember what grade I got. I probably didn't get a very good one though, because it wasn't a well thought-out paper."
Of course his BIG success with FDX was sticking with the money losing concept for over three very unprofitable years.
Though some people thought a lot of illegal moves were made before FDX became profitable. Smith was even prosecuted for bank fraud based on some of the paperwork as he struggled to keep the airline from bankruptcy as creditors tried to shut him down. He was not convicted.
"We'd run out of money and we didn't have all the regulatory requirements that we needed. My half-sisters were up in arms because it looked like we were going to lose some money. Everything was going wrong, except the fundamentals of the business were proving every single day that the idea was right."
Also, please read Smith's comments - the paper in college was about a logistics system and how the post office was not good enough for keeping computers (mainframes) up for critical companies like banks.
His idea to use aircraft, in combination with trucks - did not come until years later.
[Edited 2007-09-24 04:21:36]